Comedian Billy Connolly once advised: "There's no such thing as bad weather in Scotland, only the wrong clothes."

Despite this the country remains obsessed with the weather. Many people tune in to news bulletins purely to hear the weather forecast, while dramatic meteorological changes often themselves become news headlines.

Weather has already played a part in the referendum debate, with autumn's temperate conditions one of the reasons it was selected as the best time of year for the referendum to be held, even before a specific date was decided upon.

But could the weather have a role in the referendum's outcome? And would bad weather harm or favour one side more than the other?

Polling day forecast: Christoper Blanchett, BBC weather presenter

For polling day itself, we're expecting a cloudy start but largely dry. Any showers confined to the Northern Isles.

Through the day, it will brighten up and turn quite warm in the west and south west. Highs of 21C around Glasgow and Ayrshire.

Closer to 19C for Inverness, Perth, Stirling and Dumfries.

A shade cooler and cloudier for Aberdeen, Dundee and Edinburgh, with a small risk of some light drizzle right on the east coast.

•June 1999 : While some parts of Scotland and NE England saw some rain, other parts of the country enjoyed warm and sunny weather.

Some political commentators say that rain has traditionally been more of a turnoff for Labour voters than their Conservative counterparts.

With more Conservative votes coming from the retired demographic who are free to vote at any point in the day, the Tory turnout is less adversely affected by inclement weather. But the theory is that, as Labour voters have tended to go to the polls between teatime and 22:00, after they get in from work, they are more likely to stay at home in nasty weather than go out again to face the elements.

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"There is probably something in it, because in the older industrial working class areas, people voted on their way home from work and the middle class tended to go out in the morning or lunchtime," says Mr Howard.

"So rain in the evening has always been a frightening prospect for Labour. It's probably less relevant these days but I think there's still a grain of truth to it."

He cites the 71% turnout in the 1997 general election as an example: "When people cast their minds back to the Labour landslide of 1997, they remember a warm spring day. "

What could this mean for the referendum?

With both the UK and Scottish Labour leaders fully paid up members of Better Together, and former Labour Chancellor Alistair Darling heading up the pro-union campaign, the traditional theory would seem to suggest that a lower turnout from the traditional Labour stalwart would put more of a dent in the "No" vote than their opposition.

However, with many traditional Labour voters now apparently giving their backing to the "Yes" side, it could be it would hit the pro-independence vote too.

Realistically though, given that more Scots have registered to vote in the referendum than in any previous election in history, it is unlikely that many voters will let the risk of frizzy hair or the inconvenience of a raincoat keep them at home this time around.

Is it simply a coincidence?

In any event, some experts doubt whether there is really any connection between weather and voter turnout.

Electoral behaviour expert Prof John Curtice has dismissed any link between weather and voter turnout as a myth. He asserts that the lower turnout in traditional Labour wards has more to do with the higher likelihood of social deprivation in these areas and a lack of political engagement than anything else.

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Research also doesn't appear to bear out any real link between bad weather and a reduced turnout.

Stephen Fisher, a politics lecturer at Oxford University who has studied the relationship between the weather and turnout, says: "If you made a statistical correlation and scored the weather according to how good it was and compiled a graph showing voter turnout, over the last 15 elections you don't see a correlation.

"In 2001 turnout was 59% and in 2005, 61%. The turnouts were much lower than other post-war elections, which average at 70%, but the weather was pretty good on both those election days."

However, studies in other parts of the world have shown a different experience.

Raining on Obama's parade

Researchers from across the pond claim that weather has had a direct impact in US elections, even dictating the outcome of several presidential elections, with poor weather shown to benefit the Republicans.

Ahead of the most recent presidential election with Democrat Barack Obama running against Republican Mitt Romney, an Ipsos poll showed that 28% of Democrat voters admitted bad weather would impact whether they made it to the polls, compared to 19% of Republican voters.

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Other studies have taken the weather effect so seriously that they have attempted to create an empirical formula to quantify the correlation.

A 2007 Journal of Politics study concluded that rain reduces US voter participation by a rate of just below 1% and an inch of snowfall decreases turnout by almost 0.5%. A separate study into Dutch voting habits put a 10C increase in temperate or an inch of rainfall raising or lowering the turnout by a rate of 1%.

But political scientists also admit that regional differences matter, pointing out that an inch of rain in showery Seattle doesn't impact turnout in the same way as it would in typically sunny Los Angeles.

Weather effect in Scotland

Given Scotland's often monsoon-esque conditions even in summer, it's not as if a spot of rain isn't something voters are well used to. So are Scots better at heeding Billy Connolly advice, sticking on a raincoat and simply getting on with it, than our friends in warmer and drier climes?

As elections to the Scottish Parliament are always held on the same date - the first Thursday in May - it's hard to tell whether weather has had any impact in elections in Scotland at all.

After all, it is difficult to imagine that the meteorological conditions during spring elections would vary enough to bring about a dramatic rise or fall in the number of ballot papers to count.

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This is borne out by the statistics, with voter turnout remaining fairly consistent regardless of weather conditions. Despite a damp and drizzly day during the 2011 Scottish Parliament election, turnout stood at 50.4% - just under 1.5 percentage points less than the previous election in 2007 which saw most of Scotland enjoy dry and clear conditions.

John Curtice argues that with UK elections taking place in summer or autumn, weather conditions are rarely extreme enough to have an impact.

As he puts it: "You might need to take a brolly with you or you might have sunshine, but you won't have a howling gale or snow."

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'Rain, hail or shine'

BBC's political editor Brian Taylor warns that weather is not the only obstacle that the campaigns face in trying to get voters out of the house on polling day.

"Smart politicians check on a range of factors," he says. "On election day, they all become weather watchers. Will it rain? If it does, will it deter their lot more than the other lot? Do they need to summon extra cars to ferry voters to the polls?

"If they are going canvassing, they check the TV schedule. Heaven help the eager young activist who tries knocking doors during Eastenders or the Cup Final."

It is true that the British love affair with the weather is perhaps only rivalled by an addiction to TV.

It is said that when standing for election in 1964, Harold Wilson was so concerned that Steptoe and Son would keep prospective Labour voters glued to the screen on the evening of the vote that he went to great lengths to try and persuade BBC Director General Hugh Green to re-jig the schedule.

But is the referendum a different kettle of fish to an ordinary election?

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Rarely has an issue or political debate in this country been as impassioned and heated as the one over Scottish independence.

Political commentator Anthony Howard believed that elections which are too close to call were sure ways of luring voters into polling booths, so the recent narrowing of the polls provide yet another reason to dismiss the impact of the weather as a storm in a teacup.

The BBC's Brian Taylor is also forecasting that any referendum weather worries will be "full of wind".

He says: "Given the level of engagement with this contest, I suspect the voters will turn out on 18 September rain, hail or shine. "